BNSullivan.jpg "Stripebelly Puffer (Arothron hispidus)")
Turkeyfish or lionfish? Different name, same critter
Several days ago I put up a couple of photos of a Hawaiian Turkeyfish -- as a sort of tongue-in-cheek reference to American Thanksgiving. 'Turkeyfish' is a common name for this fish -- but it is not the common name. In some circles, the same creature is called a 'Lionfish.'Some of the readers who commented on the previous post seemed to know this, and found my Turkeyfish label to be a bit confusing. Unfortunately that is one of the problems with identifying things in nature by their common names: the names are not standardized. That is why I always include the scientific name (when I know it!) as well as the common name for the marine life in the photos I post on The Right Blue. Scientific names do not vary.
The angle of the photo on this page might give a little better clue as to why this fish might have earned either of its common names. It has this habit of spreading its spiny fins when it is disturbed, a display that must have reminded someone either of a turkey's tail, or a lion's mane. That seems to be the origin of both common names for this fish and its kin.
The scientific name for this fish is Pterois sphex. It belongs to the Scorpionfish family (Scorpaenidae). A characteristic shared by the fish in this family is that they possess venomous spines. This is their defense against being gobbled up by larger predators.
This particular species is endemic to the Hawaiian Islands. In other words, it is native to Hawaii, and it is not found elsewhere naturally. There are other fish of the genus Pterois elsewhere in the world. They all look quite similar, but close examination will reveal some clear distinctions among the species.
These other fish in the genus Pterois also are referred to as Turkeyfish or Lionfish, depending on geographical location and who's doing the talking or writing. At least one leading ichthyologist (fish biologist) prefers to apply the name Turkeyfish to the genus Pterois, and the name Lionfish to a different Scorpionfish genus, but most people seem to use the two common names almost interchangeably.
Some people who commented on the previous post mentioned that they thought they had seen this fish in a saltwater aquarium, presumably away from Hawaii. They may indeed have seen this species, or they may have seen one of its similar-looking cousins -- one of the other fish of the same genus that I mentioned above.
I don't know a whole lot about the fine points of the aquarium trade, but I do know that Turkeyfish/Lionfish are valued as "ornamental fish" and are collected for sale to aquarists. In fact, the population of these fish on our coasts has been depleted noticeably over the years as commercial fish collectors scooped them up in large numbers to sell.
The individual fish in the photo on this page (and in the previous post) has lived in the same small patch for years, along with a handful more of the same species. These fish do not have a very wide range, so once a diver discovers where they live, they can reliably be found in more or less the same spot day after day, and -- with luck -- year after year.
We know this to be true in more than a theoretical sense. Along with our friend Dan, we dived the same stretch of coastline at Puako, Hawaii several days a week for years, and we came to know where all of the permanent residents lived. We know precisely where these Turkeyfish/Lionfish live -- but we're not telling.
BNSullivan930x600.jpg)
BNSullivan930x600.jpg)
You don't know jacks...
...but we do!
We know jacks (Family: Carangidae), and they are among our favorite kinds of fish. The family has many species, and everywhere in the world that we have dived we have encountered several species of jacks.
One species we've seen in numerous locations is the Bigeye Trevally (Caranx sexfasciatus). In fact we've seen these guys everywhere from the Red Sea, through the Indo-Pacific region, to Hawaii.
Bigeye Trevally - a.k.a. Bigeye Jacks - tend to gather in fairly large schools during the daylight hours. Usually they'll hang out with their gang along a dropoff or reef slope all day long.
Around dusk, they fan out into the open ocean to hunt all night as individuals. In the morning, they find their 'schoolmates' again and reconvene to spend the day near the same dropoff. Once they form up, they often swirl around in a dense pack -- a way for them to keep together and stay more or less in one place. It really is a sight to see.
Jerry likes to play with these jacks. In fact, what he likes to do is herd them. That's right, I said herd them! He discovered that he can approach a loose aggregation of these fish while they're still a bit offshore in the bottomless blue, and coax them to go more or less where he wants them to go by swimming alongside them, much like a cowboy would ride alongside a herd of cattle.
We had been diving along this particular dropoff very early in the morning for several days in a row. Each morning we had seen the jacks in more or less the same area. I was able to take quite a few shots of this very photogenic school of Bigeye Trevally, and while I was busy taking photos, Jerry was perfecting his herding skills.
I watched him for a little while and decided it would be fun to shoot a series of photos of Jerry-the-Jacks-Wrangler in action, demonstrating his fish herding skills. As you can see in the first two photos on this page, Jerry was able to herd the jacks from offshore to the edge of the reef and nudge them into a denser aggregation. These fish are ever-moving, of course, and eventually they would begin to swirl. When that happened, we'd swim out, away from the dropoff, and then look back just to watch them swirling. From that perspective it was quite a hypnotic sight.
On the morning this series of photos was taken, I had suggested ahead of time that after the jacks schooled and began swirling, Jerry try to get inside the swirl. I thought it would make an interesting photo.
Ever the cooperative model for my underwater photos, Jerry agreed to try to get inside the cyclone of Bigeye Trevally.
The fish kept swirling and swirling, and I kept on snapping the shutter, even though it was difficult to keep things in focus with all that motion. What an action sequence!
For his part, Jerry found that he could not remain stationary once he was inside the swirl. In fact, we eventually had to stop because Jerry was becoming quite dizzy!
I think the caption for this final photo in the sequence should be, "Can I stop now? Please???"
If these schooling jacks look somewhat familiar, it might be because they are also featured in the photo in the header of The Right Blue. The images were shot at Sipadan, an oceanic island in the Celebes Sea, off the coast of Borneo.
We know jacks (Family: Carangidae), and they are among our favorite kinds of fish. The family has many species, and everywhere in the world that we have dived we have encountered several species of jacks.
One species we've seen in numerous locations is the Bigeye Trevally (Caranx sexfasciatus). In fact we've seen these guys everywhere from the Red Sea, through the Indo-Pacific region, to Hawaii.Bigeye Trevally - a.k.a. Bigeye Jacks - tend to gather in fairly large schools during the daylight hours. Usually they'll hang out with their gang along a dropoff or reef slope all day long.
Around dusk, they fan out into the open ocean to hunt all night as individuals. In the morning, they find their 'schoolmates' again and reconvene to spend the day near the same dropoff. Once they form up, they often swirl around in a dense pack -- a way for them to keep together and stay more or less in one place. It really is a sight to see.
Jerry likes to play with these jacks. In fact, what he likes to do is herd them. That's right, I said herd them! He discovered that he can approach a loose aggregation of these fish while they're still a bit offshore in the bottomless blue, and coax them to go more or less where he wants them to go by swimming alongside them, much like a cowboy would ride alongside a herd of cattle.We had been diving along this particular dropoff very early in the morning for several days in a row. Each morning we had seen the jacks in more or less the same area. I was able to take quite a few shots of this very photogenic school of Bigeye Trevally, and while I was busy taking photos, Jerry was perfecting his herding skills.
I watched him for a little while and decided it would be fun to shoot a series of photos of Jerry-the-Jacks-Wrangler in action, demonstrating his fish herding skills. As you can see in the first two photos on this page, Jerry was able to herd the jacks from offshore to the edge of the reef and nudge them into a denser aggregation. These fish are ever-moving, of course, and eventually they would begin to swirl. When that happened, we'd swim out, away from the dropoff, and then look back just to watch them swirling. From that perspective it was quite a hypnotic sight.
On the morning this series of photos was taken, I had suggested ahead of time that after the jacks schooled and began swirling, Jerry try to get inside the swirl. I thought it would make an interesting photo.
Ever the cooperative model for my underwater photos, Jerry agreed to try to get inside the cyclone of Bigeye Trevally.
The fish kept swirling and swirling, and I kept on snapping the shutter, even though it was difficult to keep things in focus with all that motion. What an action sequence!
For his part, Jerry found that he could not remain stationary once he was inside the swirl. In fact, we eventually had to stop because Jerry was becoming quite dizzy!
I think the caption for this final photo in the sequence should be, "Can I stop now? Please???"If these schooling jacks look somewhat familiar, it might be because they are also featured in the photo in the header of The Right Blue. The images were shot at Sipadan, an oceanic island in the Celebes Sea, off the coast of Borneo.
Loggerhead sea turtles need further protection
Over our lifetime of diving and being around the ocean, we have had close encounters with many sea turtles. We like sharing our sea turtle stories and photos, and we know that readers of The Right Blue like them, too. We've told our readers about Green sea turtles (Chelonia mydas) in Hawaii (including a special Green sea turtle named Myrtle), and yesterday we featured a Hawksbill turtle (Eretmochelys imbricata) that we had encountered in the Red Sea. Today we'd like to introduce you to another species of sea turtle.
.jpg "Loggerhead Sea Turtle (Caretta caretta)")
Meet the Loggerhead (Caretta caretta). While there are populations of Loggerhead turtles around the world, the North Atlantic Loggerheads are genetically distinct from other populations. They are an important part of the marine ecosystem along the coasts of the southeastern United States, yet many marine scientists believe that they are on the brink of extinction.
In the past, Loggerheads were actively hunted for their meat, and their eggs were gathered as food. Today the species is protected internationally, although major threats to their survival remain. Loggerheads are most at risk from commercial fishing activities, and from degradation of their nesting grounds.
Loggerhead sea turtles become entangled in gill nets, and get caught in trawls and scallop dredges. Like all sea turtles, Loggerheads are air breathers, so they must surface from time to time in order to breathe. Entanglement in fishing gear prevents them from surfacing, so they drown. Turtles that do not drown outright often are injured in the process of struggling to escape fishing gear.
.jpg "Incidental catch: Loggerhead sea turtle (Caretta caretta)")
Fisheries that employ long-lines -- gear that consists of hundreds of baited hooks on a single line to catch fish -- also inadvertently catch Loggerheads. Long-line fishing is efficient, and is probably less ecologically damaging than trawling or dredging (in terms of 'by-catch'). Nevertheless, no one has yet discovered a method to eliminate the danger of long-lining to the sea turtles who are attracted to the bait, and who end up swallowing large steel fishing hooks along with that bait.
In the United States, there are Loggerhead nesting beaches along the Atlantic coast, particularly in North and South Carolina, Georgia, and Florida. Loggerheads also nest on beaches of States bordering the Gulf of Mexico, from Florida to Texas. Sadly, the number of nests on these beaches is declining, and in the case of Florida, the number of Loggerhead nests has declined by about 50% over the past decade -- a startling figure!
An explosion of beachfront development is partly to blame. Some coastal areas are simply being eliminated as nesting grounds as housing and commercial activities encroach on them. Other nesting areas are being damaged by pollution, and disturbed by human and motor vehicle traffic. Turtles swimming in populated areas also are more at risk from collisions with boats.
2.jpg "Volunteer removing a fish hook from a sea turtle")
Today two conservation organizations, Oceana and the Center for Biological Diversity, have petitioned the Federal government of the United States to strengthen protection for North Atlantic Loggerhead turtles. They are urging the National Marine Fisheries Service, the agency responsible for protecting Loggerheads in ocean waters, and the U.S. Fish and Wildlife Service, the agency responsible for protecting turtles on land, to change the designation of these Loggerheads from "threatened" to "endangered" under the U.S. Endangered Species Act.
In addition to the threats from commercial fishing and degradation of nesting areas mentioned above, these conservationists also believe that climate change is now impacting the survival of Loggerheads. As summarized in a press release issued by Oceana and the Center for Biological Diversity:
We have crossed paths with very few Loggerheads over the years. As a result, we had no photos of Loggerheads in our personal collection to use for this article. All of the photos accompanying today's post came from external sources. The nice Loggerhead portrait near the top of the page came from Wikimedia Commons, and the photos of the Loggerhead with the fishing hook in its mouth were supplied by Oceana. We thank the donors of these photos for allowing us to publish them on The Right Blue.
Some of the factual information in this article was derived from Oceana's report, Climate Change and Commerical Fishing: A One-Two Punch for Sea Turtles (12 page 'pdf' file), and the Loggerhead Sea Turtle 5-year Review, published in August of 2007 by the U.S. National Marine Fisheries Service, and the U.S. Fish and Wildlife Service. (67 page 'pdf' file)
.jpg "Loggerhead Sea Turtle (Caretta caretta)")
Meet the Loggerhead (Caretta caretta). While there are populations of Loggerhead turtles around the world, the North Atlantic Loggerheads are genetically distinct from other populations. They are an important part of the marine ecosystem along the coasts of the southeastern United States, yet many marine scientists believe that they are on the brink of extinction.In the past, Loggerheads were actively hunted for their meat, and their eggs were gathered as food. Today the species is protected internationally, although major threats to their survival remain. Loggerheads are most at risk from commercial fishing activities, and from degradation of their nesting grounds.
Loggerhead sea turtles become entangled in gill nets, and get caught in trawls and scallop dredges. Like all sea turtles, Loggerheads are air breathers, so they must surface from time to time in order to breathe. Entanglement in fishing gear prevents them from surfacing, so they drown. Turtles that do not drown outright often are injured in the process of struggling to escape fishing gear.
.jpg "Incidental catch: Loggerhead sea turtle (Caretta caretta)")
Fisheries that employ long-lines -- gear that consists of hundreds of baited hooks on a single line to catch fish -- also inadvertently catch Loggerheads. Long-line fishing is efficient, and is probably less ecologically damaging than trawling or dredging (in terms of 'by-catch'). Nevertheless, no one has yet discovered a method to eliminate the danger of long-lining to the sea turtles who are attracted to the bait, and who end up swallowing large steel fishing hooks along with that bait.In the United States, there are Loggerhead nesting beaches along the Atlantic coast, particularly in North and South Carolina, Georgia, and Florida. Loggerheads also nest on beaches of States bordering the Gulf of Mexico, from Florida to Texas. Sadly, the number of nests on these beaches is declining, and in the case of Florida, the number of Loggerhead nests has declined by about 50% over the past decade -- a startling figure!
An explosion of beachfront development is partly to blame. Some coastal areas are simply being eliminated as nesting grounds as housing and commercial activities encroach on them. Other nesting areas are being damaged by pollution, and disturbed by human and motor vehicle traffic. Turtles swimming in populated areas also are more at risk from collisions with boats.
2.jpg "Volunteer removing a fish hook from a sea turtle")
Today two conservation organizations, Oceana and the Center for Biological Diversity, have petitioned the Federal government of the United States to strengthen protection for North Atlantic Loggerhead turtles. They are urging the National Marine Fisheries Service, the agency responsible for protecting Loggerheads in ocean waters, and the U.S. Fish and Wildlife Service, the agency responsible for protecting turtles on land, to change the designation of these Loggerheads from "threatened" to "endangered" under the U.S. Endangered Species Act.In addition to the threats from commercial fishing and degradation of nesting areas mentioned above, these conservationists also believe that climate change is now impacting the survival of Loggerheads. As summarized in a press release issued by Oceana and the Center for Biological Diversity:
Many marine biologists fear climate change will stress loggerhead sea turtle populations even further. Climate change can cause severe storms, erosion and sea level rise, all of which can affect sea turtle nesting on beaches. Rising temperatures caused by climate change may alter the timing or location of nesting or may increase the number of female turtles, because the sex of the hatchlings is temperature dependent. Climate change may also affect sea turtles by altering ocean currents and migration routes. Finally, ocean acidification caused by rising carbon dioxide levels breaks down the shells of preferred turtle prey, such as mollusks and crustaceans, and could alter turtles' food supply.We decided to tell our readers about Loggerhead sea turtles today in support of this effort by Oceana and the Center for Biological Diversity to recruit greater protection for these magnificent animals. For more information, please visit the Sea Turtle pages on the Oceana website.
We have crossed paths with very few Loggerheads over the years. As a result, we had no photos of Loggerheads in our personal collection to use for this article. All of the photos accompanying today's post came from external sources. The nice Loggerhead portrait near the top of the page came from Wikimedia Commons, and the photos of the Loggerhead with the fishing hook in its mouth were supplied by Oceana. We thank the donors of these photos for allowing us to publish them on The Right Blue.
Some of the factual information in this article was derived from Oceana's report, Climate Change and Commerical Fishing: A One-Two Punch for Sea Turtles (12 page 'pdf' file), and the Loggerhead Sea Turtle 5-year Review, published in August of 2007 by the U.S. National Marine Fisheries Service, and the U.S. Fish and Wildlife Service. (67 page 'pdf' file)
BNSullivan.jpg "Hawksbill turtle (Eretmochelys imbricata), Red Sea")
Tips for diving in blustery weather
Over the years we have learned a lot of things about diving that are seldom taught in training courses. One of the things we have learned from experience is that the conditions on the surface are not always indicative of conditions beneath the surface, and vice versa.
For example, on a day that is very windy and blustery, surface conditions can be problematic or even dangerous, while conditions a few meters below the surface may be completely calm. A brisk wind can turn the surface into a froth, generate choppy swells, and create or enhance surface currents. In short, the surface of the sea is not a pleasant place to be when it's very windy.
Most wind-driven waves and surface currents extend only a meter or two below the surface, thus as divers descend they are very likely to find calmer conditions. Our first tip, then, is to advise divers entering the water on a blustery day to descend as quickly as possible to get below the choppiness and surface current. Regardless of whether you're entering the water from the shore, or from a boat, if a strong wind is blowing and the surface is choppy, plan ahead of time to get below immediately and wait for your dive partner(s) there, not on the surface.
When divers are underwater on a blustery day, they can look up and see the wind whipping across the surface -- just like in the photo on this page (taken at Puako, Hawaii) -- and sometimes the wind actually can be heard from below, too. Our second blustery weather diving tip is this: If you look up and see that it is windy on the surface, try to surface as near to your boat or shoreline exit point as you possibly can. In blustery conditions, do not plan on making a surface swim at the end of your dive. Swimming through chop and swells will tire you, and if there is a surface current as well, it may carry you away from where you want to go.
In fact, when we dive in very windy conditions we consider the rough surface to be the equivalent of an 'overhead environment.' The term 'overhead environment' commonly refers to a situation in which there is literally a barrier overhead preventing the diver from making a direct ascent to the surface. The usual examples are diving in cave, or inside a shipwreck. In the case of extremely rough surface conditions the barrier is not a physical one in the same sense -- you won't bump your head on it! -- nevertheless, we plan the dive as if there were a physical barrier. We consider that a direct ascent to the surface in those conditions is not an option, and we plan the dive accordingly.
In summary, when the surface conditions are extremely rough, it is unwise (to put it mildly) to be on the surface anywhere but right beside your boat, or within wading distance of your shoreline exit point. Descend immediately when entering the water, and don't surface until you are right at your boat or your shoreline exit point.
For example, on a day that is very windy and blustery, surface conditions can be problematic or even dangerous, while conditions a few meters below the surface may be completely calm. A brisk wind can turn the surface into a froth, generate choppy swells, and create or enhance surface currents. In short, the surface of the sea is not a pleasant place to be when it's very windy.
Most wind-driven waves and surface currents extend only a meter or two below the surface, thus as divers descend they are very likely to find calmer conditions. Our first tip, then, is to advise divers entering the water on a blustery day to descend as quickly as possible to get below the choppiness and surface current. Regardless of whether you're entering the water from the shore, or from a boat, if a strong wind is blowing and the surface is choppy, plan ahead of time to get below immediately and wait for your dive partner(s) there, not on the surface.When divers are underwater on a blustery day, they can look up and see the wind whipping across the surface -- just like in the photo on this page (taken at Puako, Hawaii) -- and sometimes the wind actually can be heard from below, too. Our second blustery weather diving tip is this: If you look up and see that it is windy on the surface, try to surface as near to your boat or shoreline exit point as you possibly can. In blustery conditions, do not plan on making a surface swim at the end of your dive. Swimming through chop and swells will tire you, and if there is a surface current as well, it may carry you away from where you want to go.
In fact, when we dive in very windy conditions we consider the rough surface to be the equivalent of an 'overhead environment.' The term 'overhead environment' commonly refers to a situation in which there is literally a barrier overhead preventing the diver from making a direct ascent to the surface. The usual examples are diving in cave, or inside a shipwreck. In the case of extremely rough surface conditions the barrier is not a physical one in the same sense -- you won't bump your head on it! -- nevertheless, we plan the dive as if there were a physical barrier. We consider that a direct ascent to the surface in those conditions is not an option, and we plan the dive accordingly.
In summary, when the surface conditions are extremely rough, it is unwise (to put it mildly) to be on the surface anywhere but right beside your boat, or within wading distance of your shoreline exit point. Descend immediately when entering the water, and don't surface until you are right at your boat or your shoreline exit point.
Fire coral: Another view
by B. N. Sullivan
BNSullivan.jpg "Fire coral (Millepora dichotoma), Red Sea")
After the previous post about fire coral was published, Jerry asked, "Why didn't you include a picture that shows what the whole thing looks like, instead of just some macros? You know, so that divers and snorkelers will know what fire coral looks like before they get too close."
I had to admit, I was remiss in not including such a shot. The photo at right is Jerry's choice to show fire coral as divers and snorkelers are likely to see it. (Click on the photo to enlarge.)
The fire coral species shown here is Millepora dichotoma. Like several other fire corals of the same genus, it tends to have whitish tips while the main structure of the colony has some color. Those of you who have been following this blog for some time could probably guess that this photo was taken in the Red Sea as soon as you saw those bright orange fishies. I've mentioned several times that these little fish, called Scalefin Anthias (Pseudanthias squamipinnis), are ubiquitous in the Red Sea.
We'd also like to note that the background color of this photo is pretty close to The Right Blue!
BNSullivan.jpg "Fire coral (Millepora dichotoma), Red Sea")
After the previous post about fire coral was published, Jerry asked, "Why didn't you include a picture that shows what the whole thing looks like, instead of just some macros? You know, so that divers and snorkelers will know what fire coral looks like before they get too close."I had to admit, I was remiss in not including such a shot. The photo at right is Jerry's choice to show fire coral as divers and snorkelers are likely to see it. (Click on the photo to enlarge.)
The fire coral species shown here is Millepora dichotoma. Like several other fire corals of the same genus, it tends to have whitish tips while the main structure of the colony has some color. Those of you who have been following this blog for some time could probably guess that this photo was taken in the Red Sea as soon as you saw those bright orange fishies. I've mentioned several times that these little fish, called Scalefin Anthias (Pseudanthias squamipinnis), are ubiquitous in the Red Sea.
We'd also like to note that the background color of this photo is pretty close to The Right Blue!
Fire Coral: Look, but do not touch
by B. N. Sullivan
BNSullivan.jpg "Caribbean fire coral (Millepora alcicornis)")
When is a coral not a coral? When it is a fire coral.
Fire corals (Family: Milleporidae) look like corals, and that's how they came to be called corals, although some biological characteristics related to their life cycle set them apart distinctly from true corals.
Fire corals are reef builders just like true corals. They secrete a calcareous skeleton. They take on a variety of different shapes ranging from lacy branches (like the example in the first photo on this page), to plate-like structures, to crusts that can cover other things growing on the reef, such as sea fans.
Fire corals and true corals do belong to the same phylum (Cnidaria). A characteristic that all Cnidarians have in common are nematocysts.
Nematocysts are tiny structures on the surface tissue of the organism that are used to capture food, and to defend against predators. Nematocysts actually are very cool structures -- one of nature's engineering marvels. They consist of a fine tube, inside of which is a little coiled thread with microscopic barbs on the end. When something touches the end of the nematocyst it fires the barbed thread into whatever has touched it, just like a little harpoon fired from a harpoon gun.
BNSullivan.jpg "Macro photo of fire coral showing the dactylozooids")
The second photo on this page is an enlarged 1:1 macro shot of fire coral. The little hair-like structures on the surface (called dactylozooids) are armed with the nematocysts. Touching those little hair-like structures triggers the nematocysts to fire. Click on that photo to see an even larger, more magnified version.
The nematocysts of fire corals carry a toxin that is intended to paralyze the minute bits of plankton that are the fire coral's prey. The toxin also causes pain to predators. Divers who touch or even accidentally brush against fire coral, experience a painful sting that burns like all get out -- thus the name fire coral.
Marine biologists who study these kinds of organisms have discovered something that is useful to know. The nematocysts of fire coral (and their first cousins, the hydroids) are de-activated by acids. Thus, it's a very good idea for divers to include in their kits a small container of vinegar when they visit places where they may possibly encounter hydroids or fire coral. A little squirt of vinegar immediately stops the nematocysts that may still be stuck to the skin from firing.
Conversely, fresh water and soapy solutions actually aggravate the nematocysts. The last thing you want to do if you are stung by hydroids or fire coral is to rinse the skin with fresh water. It actually prompts any remaining nematocysts to fire.
If you are ever stung by hydroids or fire coral, you won't forget it. Usually a welt or rash arises immediately and stays for a week or more, burning again every time you take a shower or bath.
For the record, the fire coral in the first image on this page, is Millepora alcicornis, a Caribbean species. It was photographed in the Cayman Islands. The species in the second photo is Millepora dichotoma, photographed in the Red Sea near Sharm El-Sheikh, Egypt.
UPDATE: Here are some more fire coral articles and photos on The Right Blue:
BNSullivan.jpg "Caribbean fire coral (Millepora alcicornis)")
When is a coral not a coral? When it is a fire coral.Fire corals (Family: Milleporidae) look like corals, and that's how they came to be called corals, although some biological characteristics related to their life cycle set them apart distinctly from true corals.
Fire corals are reef builders just like true corals. They secrete a calcareous skeleton. They take on a variety of different shapes ranging from lacy branches (like the example in the first photo on this page), to plate-like structures, to crusts that can cover other things growing on the reef, such as sea fans.
Fire corals and true corals do belong to the same phylum (Cnidaria). A characteristic that all Cnidarians have in common are nematocysts.
Nematocysts are tiny structures on the surface tissue of the organism that are used to capture food, and to defend against predators. Nematocysts actually are very cool structures -- one of nature's engineering marvels. They consist of a fine tube, inside of which is a little coiled thread with microscopic barbs on the end. When something touches the end of the nematocyst it fires the barbed thread into whatever has touched it, just like a little harpoon fired from a harpoon gun.
BNSullivan.jpg "Macro photo of fire coral showing the dactylozooids")
The second photo on this page is an enlarged 1:1 macro shot of fire coral. The little hair-like structures on the surface (called dactylozooids) are armed with the nematocysts. Touching those little hair-like structures triggers the nematocysts to fire. Click on that photo to see an even larger, more magnified version.The nematocysts of fire corals carry a toxin that is intended to paralyze the minute bits of plankton that are the fire coral's prey. The toxin also causes pain to predators. Divers who touch or even accidentally brush against fire coral, experience a painful sting that burns like all get out -- thus the name fire coral.
Marine biologists who study these kinds of organisms have discovered something that is useful to know. The nematocysts of fire coral (and their first cousins, the hydroids) are de-activated by acids. Thus, it's a very good idea for divers to include in their kits a small container of vinegar when they visit places where they may possibly encounter hydroids or fire coral. A little squirt of vinegar immediately stops the nematocysts that may still be stuck to the skin from firing.
Conversely, fresh water and soapy solutions actually aggravate the nematocysts. The last thing you want to do if you are stung by hydroids or fire coral is to rinse the skin with fresh water. It actually prompts any remaining nematocysts to fire.
If you are ever stung by hydroids or fire coral, you won't forget it. Usually a welt or rash arises immediately and stays for a week or more, burning again every time you take a shower or bath.
For the record, the fire coral in the first image on this page, is Millepora alcicornis, a Caribbean species. It was photographed in the Cayman Islands. The species in the second photo is Millepora dichotoma, photographed in the Red Sea near Sharm El-Sheikh, Egypt.
UPDATE: Here are some more fire coral articles and photos on The Right Blue:
- Fire coral: Another view - Nov. 11, 2007
- Fire Coral Redux (includes a video) - July 5, 2009
BNSullivan.jpg "Jerry with some friendly Lined Butterflyfish, Honaunau, Hawaii")
Why I love macro photography: Surprises
About a month ago I said I love macro photography (ultra close-ups) for the fine details that are revealed. The example I gave then was a photo of a tiny hermit crab with hairy legs and turquoise eyes. Neither of those features could be seen with the naked eye -- much less by a pair of eyes behind the faceplate of a dive mask! Those details only became visible when the photo was enlarged.
The photo at right is another example of the kinds of surprises that sometimes appear when macro photos are enlarged. I shot this image of a mushroom-shaped leather coral (Sarcophyton sp.) -- a type of soft coral with a sort of rubbery skin -- because it caught my eye as a perfect specimen, in miniature. Only when the photo was enlarged did we notice the face of the tiny little fish that was hiding under the edge of the leather coral. Click on the photo to enlarge it even more.
This coral specimen was maybe two inches (5 cm) high, so the little fish was too tiny to see clearly. (For the photographers out there, this is a 1:2 image.) We have no idea what species the little fish with the great big eye is, but we surmise it's a juvenile of a reef species. We love the way he's hiding, but peeking out curiously, too. The image was shot during a night dive in the Celebes Sea.
Wreck of the Jolanda: Strange cargo
On April 1, 1980 a Cypriot cargo ship called the Jolanda was en route to the Jordanian Red Sea port of Aqaba. As the vessel passed by Ras Mohammed, the cape at the tip of the Sinai peninsula, it encountered very rough seas and ran aground on a reef.
The freighter took on water and sank, coming to a rest on the edge of the reef near a steep dropoff, where it reportedly teetered for several years. Finally, in 1986, a storm took the Jolanda the rest of the way over the ledge, and she sank out of sight into the depths.
The Jolanda was carrying containerized cargo, some of which spilled out onto the reef as the vessel broke up. For years, the containers and some of the cargo remained as the only sign of the wreck visible to divers at sport diving depths. We first saw the remains of the Jolanda's cargo in 1989. By that time soft corals already were growing on the broken containers.
For quite awhile, lines and cables attached to one of the more intact containers were used as a mooring for visiting dive boats. This photo was taken in April of 1991, eleven years after the Jolanda sank. On a return visit in late 1995, this particular container was gone, too.
These days not much of the Jolanda's cargo containers remain, but some of the freight that was inside the containers still can be seen littering one section of the reef. No, you're not seeing things. The Jolanda was laden with bathroom fixtures -- toilets, sinks, and bathtubs.
For decades, this cargo has been a source of amusement for divers, and especially for underwater photographers. Nearly everyone who has dived on this reef has taken a souvenir photo of this cargo.
The reef where the Jolanda sank used to be called Turtle Reef. Later it was renamed Jolanda Reef after the famous shipwreck. The name may sound a bit familiar to those who have been reading The Right Blue for awhile. It was mentioned in the story of an exhilarating dive we made in some crazy currents at Ras Mohammed.
The freighter took on water and sank, coming to a rest on the edge of the reef near a steep dropoff, where it reportedly teetered for several years. Finally, in 1986, a storm took the Jolanda the rest of the way over the ledge, and she sank out of sight into the depths.
The Jolanda was carrying containerized cargo, some of which spilled out onto the reef as the vessel broke up. For years, the containers and some of the cargo remained as the only sign of the wreck visible to divers at sport diving depths. We first saw the remains of the Jolanda's cargo in 1989. By that time soft corals already were growing on the broken containers.For quite awhile, lines and cables attached to one of the more intact containers were used as a mooring for visiting dive boats. This photo was taken in April of 1991, eleven years after the Jolanda sank. On a return visit in late 1995, this particular container was gone, too.
These days not much of the Jolanda's cargo containers remain, but some of the freight that was inside the containers still can be seen littering one section of the reef. No, you're not seeing things. The Jolanda was laden with bathroom fixtures -- toilets, sinks, and bathtubs.
For decades, this cargo has been a source of amusement for divers, and especially for underwater photographers. Nearly everyone who has dived on this reef has taken a souvenir photo of this cargo.The reef where the Jolanda sank used to be called Turtle Reef. Later it was renamed Jolanda Reef after the famous shipwreck. The name may sound a bit familiar to those who have been reading The Right Blue for awhile. It was mentioned in the story of an exhilarating dive we made in some crazy currents at Ras Mohammed.
Since you've asked: Answers to readers' questions
You may have noticed a tab that says "Contact" up there on the navigation bar in the header. If you click on it, a form opens where you can type a private message to us.
Most of the messages we've had so far have been greetings from family and friends who didn't want to post a public comment, but wanted us to know they had visited The Right Blue. Other messages actually have been questions, which we have answered privately (as long as the questioners left an email address).
Some of the questions we get reflect curiosity about who we are and how we got to travel to so many places and do all these dives. One questioner asked it this way:
Joking aside, please realize first that the stories and photos we feature here represent decades of diving experiences. As we explain on our About page, The Right Blue is essentially a memoir of our thousands of dives, so many of our stories are about events that happened quite a while ago. Indeed, we really did go to all those places, but we did so over a long period of time.
I should mention as well that we both did international work for most of our careers. Naturally that entailed a lot of travel, plus several stints of living overseas for years at a time. Some of the places we've dived may seem exotic, but they were relatively near to where we were living during a certain period, not halfway around the world. Many of our dive trips actually were tagged onto the end of business trips. In fact, we came to be quite well known for doing that!
Another question we have been asked repeatedly is whether we are instructors of either diving or underwater photography. The answer to both those questions is "no." Over the years we have coached many new divers and photographers, but we have never taught diving or photography in a formal way, nor do we intend to. We'll leave the teaching to the very well qualified folks who do that for a living.
Although we never pursued instructor training, we both are divemasters. We decided to get our divemaster licenses not because we wanted to work as divemasters or dive guides, but because it made our lives easier when we traveled to dive, especially after I began taking pictures underwater.
As a rule, underwater photographers do not like to dive with groups. For one thing, photographers like to move along at their own pace (and sometimes that means staying in one spot for the entire dive). Also, groups of divers are likely to scare off some of the critters the photographer wants to shoot, and they can stir up silt and sand, blow a lot of bubbles, or accidentally swim into the background of a scene at the wrong moment -- all of which can end up spoiling a shot.
It is customary for dive centers and charter boats all over the world to take divers in small groups to see the underwater sights, led by a qualified guide, for safety reasons. We discovered, however, that most operations will allow divers who are licensed instructors or divemasters in their own right to go off on their own if they wish, following a single check-out dive to verify skill level and familiarity with conditions. The reasoning is that if you are officially qualified to manage or train other divers, then you must be qualified to look after yourself. (In many cases, this boils down to a liability question.)
We went through divemaster training as a means to an end: We wanted to be able to manage our own dives if we wished to, regardless of where we were in the world. As it turned out, it opened other doors for us as well, but independence was the real reason we became divemasters.
Most of the messages we've had so far have been greetings from family and friends who didn't want to post a public comment, but wanted us to know they had visited The Right Blue. Other messages actually have been questions, which we have answered privately (as long as the questioners left an email address).
Some of the questions we get reflect curiosity about who we are and how we got to travel to so many places and do all these dives. One questioner asked it this way:
"How do you get to go to all these places? Are you independently wealthy or something?"Independent, yes; wealthy, no.
Joking aside, please realize first that the stories and photos we feature here represent decades of diving experiences. As we explain on our About page, The Right Blue is essentially a memoir of our thousands of dives, so many of our stories are about events that happened quite a while ago. Indeed, we really did go to all those places, but we did so over a long period of time.I should mention as well that we both did international work for most of our careers. Naturally that entailed a lot of travel, plus several stints of living overseas for years at a time. Some of the places we've dived may seem exotic, but they were relatively near to where we were living during a certain period, not halfway around the world. Many of our dive trips actually were tagged onto the end of business trips. In fact, we came to be quite well known for doing that!
Another question we have been asked repeatedly is whether we are instructors of either diving or underwater photography. The answer to both those questions is "no." Over the years we have coached many new divers and photographers, but we have never taught diving or photography in a formal way, nor do we intend to. We'll leave the teaching to the very well qualified folks who do that for a living.
Although we never pursued instructor training, we both are divemasters. We decided to get our divemaster licenses not because we wanted to work as divemasters or dive guides, but because it made our lives easier when we traveled to dive, especially after I began taking pictures underwater.
As a rule, underwater photographers do not like to dive with groups. For one thing, photographers like to move along at their own pace (and sometimes that means staying in one spot for the entire dive). Also, groups of divers are likely to scare off some of the critters the photographer wants to shoot, and they can stir up silt and sand, blow a lot of bubbles, or accidentally swim into the background of a scene at the wrong moment -- all of which can end up spoiling a shot.
It is customary for dive centers and charter boats all over the world to take divers in small groups to see the underwater sights, led by a qualified guide, for safety reasons. We discovered, however, that most operations will allow divers who are licensed instructors or divemasters in their own right to go off on their own if they wish, following a single check-out dive to verify skill level and familiarity with conditions. The reasoning is that if you are officially qualified to manage or train other divers, then you must be qualified to look after yourself. (In many cases, this boils down to a liability question.)
We went through divemaster training as a means to an end: We wanted to be able to manage our own dives if we wished to, regardless of where we were in the world. As it turned out, it opened other doors for us as well, but independence was the real reason we became divemasters.